news," we want to tell you about a courtroom brewing about your e-mail and privacy. Google being sued because their computers read your e-mails, so they can send you advertising. How obvious is this advertising? Abc's dan harris tried a little e-mail experiment. Reporter: To test how sophisticated google is at scanning our email, and sending us ads, I went all the way down the hallway here at abc news headquarters. And enlisted my friend and weekend gma colleague, ron claiborne. As we hatched a plan to go for chinese food tomorrow after the show, ron wrote that he needed someone to take care of his dog. And boom, dog boarding and daycare. Reporter: Then, when ron wrote that he should rent a car. Boom, discount car rentals from car rentals.Com they are on you, man. Are you the nsa leaker edward snowden by chance? It feels like it. Reporter: When I sent ron an email about bed bugs, he got ads for exterminators. When he sent me a note about needing investment advice, an ad from adviser world.Com. I figured there would be. Google says they're not the only comp doing this and they are open about their practices. They point out they don't have people reading your e-mails. Computers do that job. We knew it, but never seen it in real time. Right, amazing in realtime. Thank you dan harris and rob

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